bounce_notify_verp.c

[詳解]

/*++
/* NAME
/*  bounce_notify_verp 3
/* SUMMARY
/*  send non-delivery report to sender, server side
/* SYNOPSIS
/*  #include "bounce_service.h"
/*
/*  int     bounce_notify_verp(flags, service, queue_name, queue_id,
/*                  encoding, smtputf8, sender,
/*                  dsn_envid, dsn_ret, verp_delims,
/*                  templates)
/*  int flags;
/*  char    *service;
/*  char    *queue_name;
/*  char    *queue_id;
/*  char    *encoding;
/*  int smtputf8;
/*  char    *sender;
/*  char    *dsn_envid;
/*  int dsn_ret;
/*  char    *verp_delims;
/*  BOUNCE_TEMPLATES *templates;
/* DESCRIPTION
/*  This module implements the server side of the bounce_notify()
/*  (send bounce message) request. The logfile
/*  is removed after and a warning is posted.
/*  The bounce recipient address is encoded in VERP format.
/*  This routine must be used for single bounces only.
/*
/*  When a message bounces, a full copy is sent to the originator,
/*  and an optional  copy of the diagnostics with message headers is
/*  sent to the postmaster.  The result is non-zero when the operation
/*  should be tried again.
/*
/*  When a bounce is sent, the sender address is the empty
/*  address.
/* DIAGNOSTICS
/*  Fatal error: error opening existing file.
/* SEE ALSO
/*  bounce(3) basic bounce service client interface
/* LICENSE
/* .ad
/* .fi
/*  The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/*  Wietse Venema
/*  IBM T.J. Watson Research
/*  P.O. Box 704
/*  Yorktown Heights, NY 10598, USA
/*--*/

/* System library. */

#include <sys_defs.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>

/* Utility library. */

#include <msg.h>
#include <vstream.h>
#include <name_mask.h>
#include <stringops.h>

/* Global library. */

#include <mail_params.h>
#include <mail_queue.h>
#include <post_mail.h>
#include <mail_addr.h>
#include <mail_error.h>
#include <verp_sender.h>
#include <bounce.h>
#include <dsn_mask.h>
#include <rec_type.h>

/* Application-specific. */

#include "bounce_service.h"

#define STR vstring_str

/* bounce_notify_verp - send a bounce, VERP style */

int     bounce_notify_verp(int flags, char *service, char *queue_name,
                       char *queue_id, char *encoding,
                       int smtputf8, char *recipient,
                       char *dsn_envid, int dsn_ret,
                       char *verp_delims, BOUNCE_TEMPLATES *ts)
{
    const char *myname = "bounce_notify_verp";
    BOUNCE_INFO *bounce_info;
    int     bounce_status = 0;
    int     postmaster_status;
    VSTREAM *bounce;
    int     notify_mask = name_mask(VAR_NOTIFY_CLASSES, mail_error_masks,
                    var_notify_classes);
    char   *postmaster;
    VSTRING *verp_buf;
    VSTRING *new_id;

    /*
     * Sanity checks. We must be called only for undeliverable non-bounce
     * messages.
     */
    if (*recipient == 0)
    msg_panic("%s: attempt to bounce a single bounce", myname);
    if (strcasecmp_utf8(recipient, mail_addr_double_bounce()) == 0)
    msg_panic("%s: attempt to bounce a double bounce", myname);

    /*
     * Initialize. Open queue file, bounce log, etc.
     */
    bounce_info = bounce_mail_init(service, queue_name, queue_id,
                   encoding, smtputf8, dsn_envid,
                   ts->failure);

    /*
     * If we have no recipient list then we can't send VERP replies. Send
     * *something* anyway so that the mail is not lost in a black hole.
     */
    if (bounce_info->log_handle == 0) {
    DSN_BUF *dsn_buf = dsb_create();
    RCPT_BUF *rcpt_buf = rcpb_create();

    dsb_simple(dsn_buf, "5.0.0", "(error report unavailable)");
    (void) DSN_FROM_DSN_BUF(dsn_buf);
    vstring_strcpy(rcpt_buf->address, "(recipient address unavailable)");
    (void) RECIPIENT_FROM_RCPT_BUF(rcpt_buf);
    bounce_status = bounce_one_service(flags, queue_name, queue_id,
                       encoding, smtputf8, recipient,
                       dsn_envid, dsn_ret, rcpt_buf,
                       dsn_buf, ts);
    rcpb_free(rcpt_buf);
    dsb_free(dsn_buf);
    bounce_mail_free(bounce_info);
    return (bounce_status);
    }
#define NULL_SENDER     MAIL_ADDR_EMPTY /* special address */
#define NULL_TRACE_FLAGS    0

    /*
     * A non-bounce message was returned. Send a single bounce, one per
     * recipient.
     */
    verp_buf = vstring_alloc(100);
    new_id = vstring_alloc(10);
    while (bounce_log_read(bounce_info->log_handle, bounce_info->rcpt_buf,
               bounce_info->dsn_buf) != 0) {
    RECIPIENT *rcpt = &bounce_info->rcpt_buf->rcpt;

    /*
     * Notify the originator, subject to DSN NOTIFY restrictions.
     * 
     * Fix 20090114: Use the Postfix original recipient, because that is
     * what the VERP consumer expects.
     */
    if (rcpt->dsn_notify != 0       /* compat */
        && (rcpt->dsn_notify & DSN_NOTIFY_FAILURE) == 0) {
        bounce_status = 0;
    } else {
        verp_sender(verp_buf, verp_delims, recipient, rcpt);
        if ((bounce = post_mail_fopen_nowait(NULL_SENDER, STR(verp_buf),
                         MAIL_SRC_MASK_BOUNCE,
                         NULL_TRACE_FLAGS,
                         smtputf8,
                         new_id)) != 0) {

        /*
         * Send the bounce message header, some boilerplate text that
         * pretends that we are a polite mail system, the text with
         * reason for the bounce, and a copy of the original message.
         */
        if (bounce_header(bounce, bounce_info, STR(verp_buf),
                  NO_POSTMASTER_COPY) == 0
            && bounce_boilerplate(bounce, bounce_info) == 0
            && bounce_recipient_log(bounce, bounce_info) == 0
            && bounce_header_dsn(bounce, bounce_info) == 0
            && bounce_recipient_dsn(bounce, bounce_info) == 0)
            bounce_original(bounce, bounce_info, dsn_ret ?
                    dsn_ret : DSN_RET_FULL);
        bounce_status = post_mail_fclose(bounce);
        if (bounce_status == 0)
            msg_info("%s: sender non-delivery notification: %s",
                 queue_id, STR(new_id));
        } else
        bounce_status = 1;

        /*
         * Stop at the first sign of trouble, instead of making the
         * problem worse.
         */
        if (bounce_status != 0)
        break;

        /*
         * Optionally, mark this recipient as done.
         */
        if (flags & BOUNCE_FLAG_DELRCPT)
        bounce_delrcpt_one(bounce_info);
    }

    /*
     * Optionally, send a postmaster notice, subject to notify_classes
     * restrictions.
     * 
     * This postmaster notice is not critical, so if it fails don't
     * retransmit the bounce that we just generated, just log a warning.
     */
#define SEND_POSTMASTER_SINGLE_BOUNCE_NOTICE (notify_mask & MAIL_ERROR_BOUNCE)

    if (SEND_POSTMASTER_SINGLE_BOUNCE_NOTICE) {

        /*
         * Send the text with reason for the bounce, and the headers of
         * the original message. Don't bother sending the boiler-plate
         * text. This postmaster notice is not critical, so if it fails
         * don't retransmit the bounce that we just generated, just log a
         * warning.
         */
        postmaster = var_bounce_rcpt;
        if ((bounce = post_mail_fopen_nowait(mail_addr_double_bounce(),
                         postmaster,
                         MAIL_SRC_MASK_BOUNCE,
                         NULL_TRACE_FLAGS,
                         smtputf8,
                         new_id)) != 0) {
        if (bounce_header(bounce, bounce_info, postmaster,
                  POSTMASTER_COPY) == 0
            && bounce_recipient_log(bounce, bounce_info) == 0
            && bounce_header_dsn(bounce, bounce_info) == 0
            && bounce_recipient_dsn(bounce, bounce_info) == 0)
            bounce_original(bounce, bounce_info, DSN_RET_HDRS);
        postmaster_status = post_mail_fclose(bounce);
        if (postmaster_status == 0)
            msg_info("%s: postmaster non-delivery notification: %s",
                 queue_id, STR(new_id));
        } else
        postmaster_status = 1;

        if (postmaster_status)
        msg_warn("%s: postmaster notice failed while bouncing to %s",
             queue_id, recipient);
    }
    }

    /*
     * Examine the completion status. Delete the bounce log file only when
     * the bounce was posted successfully, and only if we are bouncing for
     * real, not just warning.
     */
    if (bounce_status == 0 && mail_queue_remove(service, queue_id)
    && errno != ENOENT)
    msg_fatal("remove %s %s: %m", service, queue_id);

    /*
     * Cleanup.
     */
    bounce_mail_free(bounce_info);
    vstring_free(verp_buf);
    vstring_free(new_id);

    return (bounce_status);
}